Soluble HLA-G molecules in follicular fluid: A tool for oocyte selection in IVF?

• Published in: Journal of reproductive immunology Vol. 74; no. 1; pp. 133 - 142
• Main Authors: Rizzo, R, Fuzzi, B, Stignani, M, Criscuoli, L, Melchiorri, L, Dabizzi, S, Campioni, D, Lanza, F, Marzola, A, Branconi, F, Noci, I, Baricordi, O.R
• Format: Journal Article
• Language: English
• Published: Shannon Elsevier Ireland Ltd 01.06.2007; Elsevier Science
• Subjects: Biological and medical sciences; Blotting, Western; Embryo; Embryo Implantation; Embryology: invertebrates and vertebrates. Teratology; Enzyme-Linked Immunosorbent Assay; Female; Fertilization in Vitro - methods; Follicular fluid; Follicular Fluid - immunology; Fundamental and applied biological sciences. Psychology; Histocompatibility Antigens Class I - analysis; Histocompatibility Antigens Class I - physiology; HLA Antigens - analysis; HLA Antigens - physiology; HLA-G; HLA-G Antigens; Humans; Immunohistochemistry; IVF; Male; Obstetrics and Gynecology; Pregnancy; Sperm Injections, Intracytoplasmic; Zygote - immunology; IVF; Embryo; Follicular fluid; HLA-G; Ovarian follicular fluid; HLA-System; Selection; Assisted procreation; Germinal cell; In vitro fertilization embryo transfer; Vertebrata; Mammalia; Oocyte; Tool
• ISSN: 0165-0378; 1872-7603
• DOI: 10.1016/j.jri.2007.02.005

Abstract Currently, different approaches are used to select oocytes for in vitro fertilization (IVF) procedures, but they do not assure a significant association with the pregnancy outcome. Since several studies have proposed the expression of HLA-G antigens in early embryos to be a possible marker of elevated implantation rate, we have investigated the presence of soluble HLA-G molecules in 50 follicular fluids (FFs). The results have shown soluble HLA-G antigens (sHLA-G) in 19/50 (38%) FFs. Furthermore, we have related the presence of sHLA-G molecules in FFs to detection of the soluble antigens in culture supernatants of the corresponding fertilized oocyte, evidencing a significant relationship ( p = 1.3 × 10−6 ; Fisher exact p -test). Specific ELISA and Western blot approaches identified both HLA-G5 and soluble HLA-G1 molecules in FFs while immunocytochemical analysis indicated polymorphonuclear-like and granulosa cells as responsible for production of sHLA-G1 and HLA-G5 molecules. In contrast, only sHLA-G1 antigens were detected in culture supernatants of fertilized oocytes. Overall, these results suggest a role for sHLA-G molecules in the ovulatory process and propose the FFs analysis for sHLA-G molecule presence as a useful tool for oocyte selection in IVF.